Trans-cinnamate 4-monooxygenase explained

trans-cinnamate 4-monooxygenase
Ec Number:	1.14.14.91
Cas Number:	9077-75-2
Go Code:	0016710

In enzymology, a trans-cinnamate 4-monooxygenase is an enzyme that catalyzes the chemical reaction

trans-cinnamate + NADPH + H⁺ + O₂

\rightleftharpoons 4-hydroxycinnamate + NADP⁺ + H₂O

The 4 substrates of this enzyme are trans-cinnamate, NADPH, H⁺, and O₂, whereas its 3 products are 4-hydroxycinnamate, NADP⁺, and H₂O. This enzyme participates in phenylalanine metabolism and phenylpropanoid biosynthesis. It employs one cofactor, heme.

This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O₂ as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with NADH or NADPH as one donor, and incorporation of one atom o oxygen into the other donor.

Nomenclature

The systematic name of this enzyme class is trans-cinnamate,NADPH:oxygen oxidoreductase (4-hydroxylating). Other names in common use include:

• cinnamic acid 4-hydroxylase,
• oxygenase, cinnamate 4-mono-,
• CA4H (gene name),
• CYP73A1 (gene name),
• cytochrome P450 cinnamate 4-hydroxylase,
• cinnamate 4-hydroxylase,
• cinnamate 4-monooxygenase,
• cinnamate hydroxylase,
• cinnamic 4-hydroxylase,
• cinnamic acid 4-monooxygenase,
• cinnamic acid p-hydroxylase,
• hydroxylase, cinnamate 4-,
• t-cinnamic acid hydroxylase,
• trans-cinnamate 4-hydroxylase, and
• trans-cinnamic acid 4-hydroxylase.

Further reading

• Potts JR, Weklych R, Conn EE, Rowell J . 1974 . The 4-hydroxylation of cinnamic acid by sorghum microsomes and the requirement for cytochrome P-450 . J. Biol. Chem. . 249 . 5019 - 26 . 4153152 . 16 .
• Russell DW, Conn EE . Eric Conn (biochemist) . 1967 . The cinnamic acid 4-hydroxylase of pea seedlings . Arch. Biochem. Biophys. . 122 . 256 - 8 . 4383827 . 10.1016/0003-9861(67)90150-6 . 1 .
• Petersen M . Cinnamic acid 4-hydroxylase from cell cultures of the hornwort Anthoceros agrestis . Planta . 217 . 1 . 96–101 . May 2003 . 12721853 . 10.1007/s00425-002-0960-9 .